Spacecraft typically employ one or more structures have relatively large dimensions when operational. Among these structures are solar sails, antennas, solar arrays, heat shields, de-orbiters and the like. Typically, these structures transition between an undeployed state in which the structures do not provide or only provide in a limited fashion the desired function for the spacecraft and a deployed state in which the structures provide the desired function for the spacecraft. In many instances, these structures must occupy a constrained space when in the undeployed state. In some instances, the structure may have the same dimensions in the constrained space of the undeployed state as the structure has in deployed state. For instance, the dimensions of a flat solar wing that is disposed parallel to the flat side of a spacecraft in an undeployed state has the same dimensions when disposed so as to extend perpendicular to the side of the spacecraft in the deployed state. In other instances, the structure has different dimensions in the constrained space of the undeployed state than the structure has in the deployed state. For example, the dimensions of a solar wing comprised of a number of rigid solar panels that are connected to one another with hinges that allow the panels to be folded in an accordion fashion in the undeployed state are different than when the panels are unfolded to realize a planar structure in the deployed state. For various reasons, structures that employ flexible membranes in which the dimensions in the constrained space of the undeployed state are different than in the deployed state are also employed. Among the reasons for employing flexible membranes are situations in which the dimensions of the constrained space associated with the undeployed state render other approaches problematic. For instance, a structure in which an antenna array structure is implemented with a flexible membrane can more readily occupy a dimensionally irregular space than an antenna array structure implemented with a plurality of hinged rectangular solar panels.
With respect to spacecraft structures that employ flexible membranes to realize large dimensional structures such as solar sails, antennas, solar arrays, heat shields, de-orbiters and the like, the deployment mechanisms employed in these structures have taken various forms. For instance, U.S. Pat. No. 3,530,460 discloses the use of telescoping rods to transition a reflector from an undeployed state to a deployed state. Another deployment mechanism utilizes inflatable tubes to transition a sheet that supports solar cells from an undeployed state to a deployed state. See U.S. Pat. No. 6,568,640.